Fast-dry, high solids coatings based on modified alkyd resins

ABSTRACT

An ambient oxidative cure composition based on an acrylate functionalized alkyd resin is described. A method of preparing an ambient oxidative cure composition based on an acrylate functionalized alkyd resin is also described. Such ambient oxidative cure compositions may be used in, for example, fast drying, high solid paint or enamel compositions or formulations.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a Continuation patent application under 37 C.F.R.1.53(b), of copending prior application Ser. No. 09/596,269, filed onJun. 16, 2000, which claims benefit of priority under 35 U.S.C. § 119(e)to U.S. Provisional Application No. 60/140,788 filed on Jun. 25, 1999,which is herein incorporated in its entirety by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to an ambient oxidative cure compositioncontaining an acrylate functionalized alkyd resin. The invention alsorelates to methods of preparing an ambient oxidative cure compositioncontaining an acrylate functionalized alkyd resin. Such compositions areuseful in preparing fast-dry, high solids coatings such as, for example,enamels.

2. Description of Related Art

In recent years, considerable effort has been expended by the coatingsindustry to develop low or zero VOC containing coating formulations.Regulations to limit the amount of VOC content of industrial coatingshave encouraged research and development to explore new technologiesdirected at reducing solvent emissions from industrial solvent-basedcoatings operations such as automotive, appliance, general metal,furniture, and the like. However, while the move to reduced organicsolvent-based compositions brings health and safety benefits, theselower VOC coating compositions must still meet or exceed the performancestandards expected from solvent-based compositions.

Alkyd resins are one of the most common binders used for ambient-cure,solvent-based coatings. Resistance properties of traditionalsolvent-borne alkyd resins are developed via autooxidative crosslinkingof the alkyd film. Crosslinking occurs when the activated methylenegroups in the unsaturated fatty acids or oils of the alkyd are oxidizedin air to give hydroperoxides which subsequently decompose to generatefree radicals for various crosslinking mechanisms. This oxidativecrosslinking process is commonly accelerated by adding driers such as,for example, various salts of cobalt, zirconium, calcium, and manganese.However, while alkyd resins have shown, and continue to show promise,they have relatively slow “dry” and/or cure times, particularly atambient temperatures. Various modifications have been made to alkydresins in an attempt to address such concerns.

One such attempt includes polymerization of an alkyd resin with a vinylcompound, such as styrene or methyl methacrylate, via a free-radicalreaction to produce a vinyl-alkyd copolymer or a vinyl alkyd. Vinylalkyd resins generally have a higher molecular weight and a higher T_(g)and accordingly produce coatings with reduced tack-free time (solventevaporation). However, the through-dry time (oxidation of the film) ofsuch coatings takes longer due to the decreased degree of unsaturationin the alkyd as a result of copolymerization with the vinyl compound. Inaddition, paint formulations which contain vinyl alkyd resins require agreater amount of solvent due to increased molecular weight and T_(g) ofthe vinyl alkyd.

JP 48085628 describes a modified alkyd resin using glycidyl acrylate,glycidyl methacrylate, or its derivative. Drying oil-modified alkydresins having —CO₂H groups and an oil length of 20-80 are treated withglycidyl acrylate, glycidyl methacrylate, or its derivative in thepresence of a polymerization inhibitor. The resulting resin is mixedwith a photosensitizer or photoinitiator to give a coating compositionwhich hardens with UV irradiation. However, these resin compositionswere not suitable for ambient oxidative cure, high-solids coatingapplications.

Thus there still exists a need in the art for a modified orfunctionalized alkyd resin capable of undergoing crosslinking upon filmformation which can be used to prepare ambient oxidative cure, fast-dryand high solids coatings having low VOC. Such coatings would exhibit theproperties and advantages of high VOC coatings.

SUMMARY OF THE INVENTION

The present invention answers this need by providing an ambientoxidative cure composition comprising an acrylate functionalized alkydresin, at least one drier, and an organic solvent. An acrylatefunctionalized alkyd resin is an alkyd resin modified with glycidylacrylate via a non-free radical reaction where the glycidyl moiety ofthe glycidyl acrylate is the reaction moiety such that the resultingalkyd resin contains terminal reactive acrylate groups or moieties. Suchan acrylate functionalized alkyd resin exhibits superior through-drytime properties. Furthermore, an acrylate functionalized alkyd resin ofthe invention exhibits superior tack-free time properties whichpreviously could only be improved by increasing the molecular weight andT_(g) of the alkyd resin. Since the amount of VOC generally added toalkyd resin compositions and/or formulations is directly related to themolecular weight and T_(g) of the alkyd resin, compositions orformulations containing an acrylate functionalized alkyd resin of theinvention would require less VOC.

The invention also relates a method of preparing an ambient oxidativecure composition comprising the step of contacting an acrylatefunctionalized alkyd resin with at least one drier in the presence of anorganic solvent.

DETAILED DESCRIPTION OF THE INVENTION

The invention provides an ambient oxidative cure composition comprisingan acrylate functionalized alkyd resin, at least one drier, and anorganic solvent. In a preferred embodiment of the invention, an ambientoxidative cure composition contains about 50 to about 85 wt % based onthe total weight of the composition of an acrylate functionalized alkydresin, about 10 to about 50 wt % based on the total weight of thecomposition of an organic solvent, and about 0.01-1.0 wt % based on thetotal weight of the composition of at least one drier. According to theinvention, an ambient oxidative cure composition exhibits improvedtack-free and through-dry times, and may be used in enamel compositionshaving reduced VOC and fast through-dry and tack-free times.

An acrylate functionalized alkyd resin is an alkyd resin containingterminal reactive acrylate groups or moieties. An acrylatefunctionalized alkyd resin is the reaction product of a hydroxylfunctional alkyd resin, an acid anhydride, and a glycidyl acrylate ofwhich the glycidyl moiety is the reactive moiety. In a preferredembodiment of the invention, the acrylate functionalized alkyd resincomprises the reaction product of: (i) about 79 to about 95 wt % of ahydroxyl functional alkyd resin; (ii) about 2 to about 8 wt % of an acidanhydride; and (iii) about 3 to about 13 wt % of a glycidyl acrylate,each as described herein, wherein the weight percents are based on thetotal weight of (i), (ii) and (iii).

A hydroxyl functional alkyd resin may be any alkyd resin containinghydroxyl functionality known in the art. The hydroxyl functional alkydmay be prepared by reacting a diol, a polyol, a diacid, a monofunctionalacid, and a fatty acid, fatty ester, or naturally occurring-partiallysaponified oil, optionally, in the presence of a catalyst. Preferably, ahydroxyl functional alkyd resin is the reaction product of(a) 0 to about30 mole % of a diol, (b) about 10 to about 40 mole % of a polyol, (c)about 20 to about 40 mole % of a diacid, (d) 0 to about 10 mole % of amonofunctional acid, (e) about 10 to about 40 mole % of a fatty acid,fatty ester, or naturally occurring oil, and, optionally, (f) acatalyst, wherein the mole percents are based on the total moles of(a),(b), (c), (d), (e) and (f) if present. Suitable examples of each of thecomponents of the hydroxyl functional alkyd resin include those known inthe art including, but not limited to, those discussed below. Resins forSurface Coatings, Vol. 1, p. 127, ed. by P. K. T. Oldring and G.Hayward, SITA Technology, London, UK.

The fatty acid, fatty ester, or naturally occurring-partially saponifiedoil may be any fatty acid, fatty ester, or naturally occurring-partiallysaponified oil known in the art used in the formation of an alkyd resin.In a preferred embodiment, at least one monobasic fatty acid, fattyester, or naturally occurring-partially saponified oil is used andselected from the following formulae (I), (II), and (III):

In formulae (I); (II), and (III), R is a saturated or unsaturated C₈-C₂₀alkyl group. More preferably, R is one of the following unsaturated C₁₇alkyl groups:

In another embodiment, the monobasic fatty acid or fatty ester oil maybe prepared by reacting an oil or a fatty acid with a polyol. Examplesof suitable oils include sunflower oil, canola oil, dehydrated castoroil, coconut oil, corn oil, cottonseed oil, fish oil, linseed oil,oiticica oil, soya oil, tung oil, animal grease, castor oil, lard, palmkernel oil, peanut oil, perilla oil, safflower oil, tallow oil, walnutoil, and the like. Suitable examples of fatty acids alone or ascomponents of oil include, but are not limited to, tallow acid, soyaacid, myristic acid, linseed acid, crotonic acid, versatic acid, coconutacid, tall oil fatty acid (e.g. PAMOLYN 200, commercially available fromHercules), rosin acid, neodecanoic acid, neopentanoic acid, isostearicacid, 12-hydroxystearic acid, cottonseed acid, and the like.

The polyol used in the preparation of the hydroxyl functional alkydresin itself or the monobasic fatty acid or fatty ester is preferablyselected from aliphatic, alicyclic, and aryl alkyl polyols. Suitableexamples of polyols include, but are not limited to, trimethylolpropane(TMP), pentaerythritol (PE), trimethylolethane, erythritol, threitol,dipentaerythritol, sorbitol, glycerine, and the like. Preferably, thepolyol is trimethylolpropane (TMP) or pentaerythritol (PE).

In addition to the polyol, a diol may be used in the preparation of thehydroxyl functional alkyd resin. Examples of suitable diols include, butare not limited to, neopentyl glycol (NPG), ethylene glycol, propyleneglycol, diethylene glycol, triethylene glycol, tetraethylene glycol,pentaethylene glycol, hexaethylene glycol, heptaethylene glycol,octaethylene glycol, nonaethylene glycol, decaethylene glycol,1,3-propanediol, 2,4-dimethyl-2-ethyl-hexane-1,3-diol,2,2-dimethyl-1,2-propanediol, 2-ethyl-2-butyl-1,3-propanediol,2-ethyl-2-isobutyl-1,3-propanediol, 1,3-butanediol, 1,4-butanediol,1,5-pentanediol, 1,6-hexanediol, 2,2,4-tetramethyl-1,6-hexanediol,thiodiethanol, 1,2-cyclohexanedimethanol, 1,3-cyclohexanedimethanol,1,4-cyclohexanedimethanol, 2,2,4-trimethyl-1,3-pentanediol,2,2,4-tetramethyl-1,3-cyclobutanediol, p-xylenediol, hydroxypivalylhydroxypivalate, 1,10-decanediol, and hydrogenated bisphenol A.Preferably, the diol is neopentyl glycol (NPG).

The diacid or dicarboxylic acid and monofunctional or monocarboxylicacid component of the hydroxyl functional alkyd resin may be any diacidor monofunctional acid known in the art used in the formation of analkyd resin. The dicarboxylic acid may be, for example, isophthalicacid, phthalic anhydride(acid), terephthalic acid, adipic acid,tetrachlorophthalic anhydride, dodecanedioic acid, sebacic acid, azelaicacid, 1,4-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylicacid, maleic anhydride, fumaric acid, succinic anhydride, succinic acid,2,6-naphthalenedicarboxylic acid, or glutaric acid and the like.Preferably, the dicarboxylic acid is isophthalic acid, phthalicanhydride, or phthalic acid. A monofunctional acid may also be used suchas, for example, benzoic acid, acetic acid, propionic acid, and butanoicacid.

Optionally, a catalyst may be used to promote the formation of ahydroxyl functional alkyd resin. The catalyst may be any catalyst knownin the art used in the formation of an alkyd resin. Preferably, thecatalyst is an acid catalyst such as, for example, FASCAT 4100. Theamount of catalyst added promotes the formation of a hydroxyl functionalalkyd resin as described above and may be determined by routineexperimentation as understood by those skilled in the art. Preferably, acatalyst is added in amounts ranging from about 0.01-1.00 wt % based onthe amount of reactants.

A hydroxyl functional alkyd resin may be prepared at a temperature rangeof about 170-230° C., more preferably 180-220° C. and most preferably,190-210° C. In a preferred embodiment of the invention, a hydroxylfunctional alkyd resin has a hydroxyl number of about 80 to about 180 mgKOH/g, an acid number of 0 to about 10 mg KOH/g, a number averagemolecular weight of about 700 to about 2000, and a T_(g) of less thanabout 25° C.

Suitable acid anhydrides include those known in the art. Examples ofsuitable acid anhydrides include, but are not limited to, trimelliticanhydride, phthalic anhydride, maleic anhydride, and fumaric anhydride.Preferably, trimellitic anhydride is used.

The glycidyl acrylate may be any substituted or unsubstituted acrylatecontaining an epoxide or glycidyl moiety that upon reaction with ahydroxyl functional alkyd resin and an acid anhydride will produce anacrylate functionalized alkyd resin capable of effecting crosslinkingduring the curing process, each as described above. According to theinvention, upon reaction with a hydroxyl functional alkyd resin and anacid anhydride, the glycidyl moiety of the glycidyl acrylate exhibitsgreater reactivity than the acrylate moiety, i.e. it is the glycidylmoiety which undergoes reaction with the hydroxyl functional alkyd resinand acid anhydride. Suitable substituents for the acrylate portion ofthe glycidyl acrylate include C₁-C₁₈ alkyl groups to form classes ofcompounds such as, for example, alkylacrylates (e.g. methacrylates) andcrotonates. Preferably, the glycidyl acrylate is glycidyl methacrylate.

An acrylate functionalized alkyd resin may be prepared by reacting ahydroxyl functional alkyd resin with an acid anhydride, each asdescribed above, to produce a carboxyl functional alkyd resin andreacting the carboxyl functional alkyd resin with a glycidyl acrylate toproduce an acrylate functionalized alkyd resin, as described above. Anacrylate functionalized alkyd resin may be prepared at a temperaturerange of about 100-170° C., more preferably about 115-165° C., and mostpreferably, about 125-155° C.

In a preferred embodiment of the invention, an acrylate functionalizedalkyd resin is prepared by reacting (a) 0 to about 30 mole % of a diol,(b) about 10 to about 40 mole % of a polyol, (c) about 20 to about 40mole % of a diacid, (d) 0 to about 10 mole % of a monofunctional acid,in the presence of (f) a catalyst, each as described above, at about180-220° C. until the collection of the condensate (water) stops to forman intermediate alkyd; reacting the intermediate alkyd with (e) about 10to about 40 mole % of a fatty acid, fatty ester, or naturallyoccurring-partially saponified oil, at about 190-220° C. until an acidnumber of less than about 5 is obtained to form (i) a hydroxylfunctional alkyd resin, each as described above, wherein the molepercents are based on the total moles of (a), (b), (c), (d), (e) and(f); reacting the hydroxyl functional alkyd resin (i) with about 2 toabout 8 wt % of(ii) an acid anhydride at about 150-165° C. for about 2-6hours until a clear reaction mixture is obtained and thereby form acarboxyl functional alkyd resin, each as described above; and reactingthe carboxyl functional alkyd resin with about 3 to about 12 wt % of(iii) glycidyl acrylate, at about 125-155° C. until an acid number ofless than about 5 is obtained and thereby form the desired acrylatefunctionalized alkyd resin, each as described above, wherein the weightpercents are based on the total weight of (i), (ii) and (iii).

According to the invention, the amount of organic solvent required inthe final ambient oxidative cure composition is reduced since theacrylate functionalized alkyd resin, as described above, exhibits lowerT_(g) values. The organic solvent may be any suitable solvent. Examplesof suitable organic solvents include, but are not limited to, xylene,benzene, toluene, and mineral spirits. Preferably, the organic solventis xylene. An ambient oxidative cure composition of the invention has ahigh solids content of generally greater than about 70%.

The drier of an ambient cure composition of the invention may be anydrier known in the art. Examples of suitable driers include, but are notlimited to, various salts of cobalt, zirconium, calcium, zinc, andmanganese. Preferably, the drier is a cobalt drier. Mixtures of driers,i.e. a drier system, may also be used.

In a preferred embodiment of the invention, an ambient oxidative curecomposition, as described above, may also contain at least one pigmentto form an ambient oxidative cure enamel composition. Preferably, thepigment is present in an amount of about 30 to about 60 wt % based onthe total weight of the composition. Examples of suitable pigmentsinclude those recognized by those of ordinary skill in the art ofsurface coatings. For example, the pigment may be a typical organic orinorganic pigment, especially those set forth by the Colour Index, 3dEd., 2d Rev., 1982, published by the Society of Dyers and Colourists inassociation with the American Association of Textile Chemists andColorists. Other examples of suitable pigments include, but are notlimited to, the following: titanium dioxide, barytes, clay, or calciumcarbonate, CI Pigment White 6 (titanium dioxide); CI Pigment Red 101(red iron oxide); CI Pigment Yellow 42, CI Pigment Blue 15, 15:1, 15:2,15:3, 15:4 (copper phthalocyanines); CI Pigment Red 49:1; and CI PigmentRed 57:1. Preferably, the pigment is titanium oxide. Colorants such as,for example, phthalocyanine blue, molybdate orange, or carbon black maybe also be added to the ambient cure oxidative cure enamel composition.

An ambient oxidative cure composition, preferably, an ambient oxidativecure enamel composition, may be coated onto a substrate and cured usingtechniques known in the art (e.g. by spray-applying 3 to 4 mils of wetcoating onto a metal panel, and heating in a 150° C. forced air oven for30 minutes). The substrate may be any common substrate such as, forexample, paper, polyester films such as, for example, polyethylene orpolypropylene, metals such as, for example, aluminum or steel, glass,urethane elastomers, primed (painted) substrates, and the like. Anambient oxidative cure composition of the invention may be cured at roomtemperature (ambient cure).

An ambient oxidative cure composition of the invention may furthercontain at least one coating additive in order to, for example, enhancethe composition's drying efficiency Examples of suitable coatingadditives include, but are not limited to, leveling and flow controlagents such as silicones, fluorocarbons or cellulosics; extenders;plasticizers; flatting agents; pigment wetting and dispersing agents;ultraviolet (UV) absorbers; UV light stabilizers; defoaming andantifoaming agents; anti-settling, anti-sag and bodying agents;anti-skinning agents; anti-flooding and anti-floating agents; andcorrosion inhibitors. Specific examples of such additives can be foundin Raw Materials Index, published by the National Paint & CoatingsAssociation, 1500 Rhode Island Avenue, NW., Washington, D.C. 20005.Further examples of such additives may be found in U.S. Pat. No.5,371,148.

Examples of flatting agents include, but are not limited to, syntheticsilica, available from the Davison Chemical Division of W. R. Grace &Company as SYLOID ®; polypropylene, available from Hercules Inc., asHERCOFLAT ®; synthetic silicate, available from J. M. Huber Corporation,as ZEOLEX ®.

Examples of dispersing agents include, but are not limited to, sodiumbis(tridecyl) sulfosuccinnate, di(2-ethyl hexyl) sodium sulfosuccinnate,sodium dihexylsulfosuccinnate, sodium dicyclohexyl sulfosuccinnate,diamyl sodium sulfosuccinnate, sodium diisobutyl sulfosuccinnate,disodium iso-decyl sulfosuccinnate, disodium ethoxylated alcohol halfester of sulfosuccinic acid, disodium alkyl amido polyethoxysulfosuccinnate, tetra-sodium N-(1,2-dicarboxyethyl)-N-octadecylsulfosuccinnamate, disodium N-octasulfosuccinnamate, sulfatedethoxylated nonylphenol, 2-amino-2-methyl-1-propanol, and the like.

Examples of viscosity, suspension, and flow control agents include, butare not limited to, polyaminoamide phosphate, high molecular weightcarboxylic acid salts of polyamine amides, and alkylene amine salts ofan unsaturated fatty acid, all available from BYK Chemie U.S.A. as ANTITERRA ®. Further examples include, but are not limited to, polysiloxanecopolymers, polyacrylate solution, cellulose esters, hydroxyethylcellulose, hydroxypropyl cellulose, polyamide wax, polyolefin wax,hydroxypropyl methyl cellulose, polyethylene oxide, and the like.

Several proprietary antifoaming agents are commercially available andinclude, but are not limited to, BUBREAK ® of Buckman Laboratories Inc.;BYK ® of BYK Chemie, U.S.A.; FOAMASTER ® and NOPCO ® of HenkelCorp./Coating Chemicals; DREWPLUS ® of the Drew Industrial Division ofAshland Chemical Company; TRYSOL ® and TROYKYD ® of Troy ChemicalCorporation; and SAG ® of Union Carbide Corporation.

Examples of U.V. absorbers and U.V. light stabilizers include, but arenot limited to, substituted benzophenone, substituted benzotriazoles,hindered amines, and hindered benzoates, available from AmericanCyanamid Company as CYASORB UV ®, anddiethyl-3-acetyl-4-hydroxy-benzyl-phosphonate, 4-dodecyloxy-2-hydroxybenzophenone, and resorcinol monobenzoate.

Examples of solvents are well known and include, but are not limited to,ethanol, n-propanol, isopropanol, n-butanol, sec-butanol, isobutanol,ethylene glycol monobutyl ether, propylene glycol n-butyl ether,propylene glycol methyl ether, propylene glycol monopropyl ether,dipropylene glycol methyl ether, diethylene glycol monobutyl ether,trimethylpentanediol mono-isobutyrate, ethylene glycol mono-octyl ether,diacetone alcohol, TEXANOL® ester alcohol (Eastman Chemical Company),and the like. Such solvents may also include reactive solvents such as,for example, diallyl phthalate, SANTOLINK XI-100 ® polyglycidyl allylether from Monsanto, and others as described in U.S. Pat. Nos. 5,349,026and 5,371,148.

The invention also provides a method of preparing an ambient oxidativecure composition comprising the step of contacting an acrylatefunctionalized alkyd resin with at least one drier in the presence of anorganic solvent, each as described above. An acrylate functionalizedalkyd resin may be prepared as described above. Preferably, the acrylatefunctionalized alkyd resin is reacted with at least one drier present inamount of about 0.01-1.0 wt % in an organic solvent.

The following examples are given to illustrate the invention. It shouldbe understood, however, that the invention is not to be limited to thespecific conditions or details described in these examples.

The examples of various coating compositions of the invention use thefollowing materials not described above:

PAMOLYN 200 a tall oil fatty acid, sold by Hercules Incorporated ofWilmington, Del.

FASCAT 4100 an esterification catalyst, sold by M&T Chemicals of Rahway,N.J.

FC-430 is a fluorocarbon additive sold by 3M Corp of St. Paul, Minn.

calcium CEM-All is a calcium carboxylate sold by OM Group of Cleveland,Ohio.

The following methods were used to evaluate the coatings and filmsprepared according to the invention.

Tack Free Cotton Test:

The coating is considered tack free if it does not pull fibers when thefilm surface is in contact with absorbent cotton fibers.

Through Dry Thumb Test:

The coating is considered through dry if it is not affected (nowrinkling) by pressing and twisting with the thumb on the surface of thefilm.

Zapon Tack Free Test:

A piece of 1 by 4 inch aluminum metal strip is bent to give a 1 by 1inch of base and at an angle such that a 5 g weight would just enough tohold the base without tilting over. This metal strip is set on thecoating film and a steel cylinder (500 g weight, 1 inch in diameter) isplaced on the base for 45 seconds. The film is considered Zapon tackfree if the aluminum strip tilts over as soon as the cylinder weight isremoved.

EXAMPLES

As described in the following examples, hydroxyl functional alkyd resins1 & 2 were synthesized and subsequently modified with glycidylmethacrylate (GMA) to form, respectively, acrylate functionalized alkydresin 1 & 2. Hydroxyl functional alkyd resin 1 was cut in xylene to 70%solids before the modification process to reduce the viscosity, whilehydroxyl functional alkyd resin 2 which had a lower T_(g) (and thereforelower viscosity) was used directly for modification.

Example 1 Preparation of Hydroxyl Functional Alkyd Resin 1

To a three-neck, round-bottom flask equipped with a mechanical stirrer,a steam-jacketed partial condenser, a Dean-Stark trap, a nitrogen inlet,and a water condenser were charged neopentyl glycol (NPG) (53.89 g, 0.52mol); trimethylolpropane (TMP) (139.87 g, 1.04 mol); isophthalic acid(IPA) (201.82 g, 1.22 mol); benzoic acid (BA) (30.37 g, 0.25 mol); andFASCAT 4100 (Atochem) (0.32 g). The mixture was allowed to react at 180°C.-220° C. until 47.5 g of the condensate (water) was obtained. Afterthe mixture was cooled, PAMOLYN 200 (Hercules) (209.06 g, 0.72 mol) andFASCAT 4100 (0.32 g) were then added. The reaction was allowed tocontinue at 190°-220° C. until an acid number of 1.8 was obtained. Theresulting resin was allowed to cool to 120° C. and xylene (246 g) addedto yield a resin solution with 70% solids.

Example 2 Preparation of Acrylate Functionalized Alkyd Resin 1

To a three-neck, round-bottom flask equipped with a mechanical stirrer,a water condenser, and a nitrogen inlet were charged the hydroxylfunctional alkyd resin 1 of Example 1 (300 g, 70%) and trimelliticanhydride (TMA) (8.9 g, 0.046 mol). The reaction mixture was stirred at150° C. for 6 hr and then allowed to cool to 110° C. Glycidylmethacrylate (GMA) (13.1 g, 0.092 mol), was subsequently added. Thereaction was allowed to continue at 150° C. for 1.5 hr to yield a clearresin with an acid number of 2.9.

Example 3 Preparation of Hydroxyl Functional Alkyd Resin 2

To a three-neck, round-bottom flask equipped with a mechanical stirrer,steam-jacked partial condenser, a Dean-Stark trap, a nitrogen inlet, anda water condenser were charged neopentyl glycol (NPG) (97.80 g, 0.94mol); pentaerythritol (PE) (70.14 g, 0.52 mol); isophthalic acid (IPA)(36.60 g, 0.22 mol); phthalic anhydride (PA) (107.22 g, 0.72 mol); andFASCAT 4100 (0.30 g). The mixture was allowed to react at 190° C.-200°C. until 19.5 g of the condensate (water) was obtained. After themixture was cooled, PAMOLYN 200 (295.77 g, 1.02 mol) and FASCAT 4100(0.30 g) were then added. The reaction was allowed to continue at 200°C. until an acid number of 0.9 was obtained. The resulting resin wasisolated neat (100% solids).

Example 4 Preparation of Acrylate Functionalized Alkyd Resin 2

To a three-neck, round-bottom flask equipped with a mechanical stirrer,a water condenser, and a nitrogen inlet were charged the hydroxylfunctional alkyd resin 2 of Example 3 (210 g) and trimellitic anhydride(TMA) (8.9 g, 0.046 mol). The reaction mixture was stirred at 165° C.for 3.5 hr and then allowed to cool to 110° C. Glycidyl methacrylate(GMA) (13.1 g, 0.092 mol), was subsequently added. The reaction wasallowed to continue at 160° C. for 2 hr to yield a clear resin with anacid number of 2.9. The resulting resin was allowed to cool to 120° C.and xylene (57 g) added to yield a resin solution having 80% solids.

Example 5 Enamel Coating Composition

A pigment grind was first prepared by using a Dispermat mixer(BYK-Chemie) to blend the acrylate functionalized alkyd resin 1 ofExample 2 (16.23 g, 71.8% in xylene), TiO (Du Pont, Ti-Pure R-900, 35.00g), FC-430 (3M, 0.16G (20% in isopropanol)) until a particle size ofHegman 7+was obtained. Next, additional acrylate functionalized alkydresin 1 (32.46, 71.8%g), cobalt drier (6%, NUODEX, Tenneco Chemicals),calcium CEM-All (4%, OM Group), and xylene (7.05 g) were added to thegrind. The mixture was further stirred to give a homogeneous whitepaint.

Enamels coating compositions based on hydroxyl functional alkyd resins 1& 2 of, respectively, Examples 1 and 3, and the acrylate functionalizedalkyd resin 2 of Example 4 were prepared similarly as in Example 5. Thesolvent content was adjusted for each enamel to give an applicableviscosity.

Example 6 Film Dry Time

In order to compare their dry times, enamels coating compositions havinghigh solids were formulated from (a) hydroxyl functional alkyd resin 1:(b) hydroxyl functional alkyd resin 2; (c) acrylate functionalized alkydresin 1; and (d) acrylate functionalized alkyd resin 2. The resultingenamels had the following % solids:

(a) hydroxyl functional alkyd resin 1: 75%;

(b) hydroxyl functional alkyd resin 2: 91%;

(c) acrylate functionalized alkyd resin 1: 75%; and

(d) acrylate functionalized alkyd resin 2: 84%.

As shown in Table I, the various dry times of the enamel compositionbased on acrylate functionalized alkyd resins were much shorter thanthose based on the hydroxyl functional alkyd resins. Hydroxyl functionalalkyd resin 2 was formulated for comparison purpose only since itsviscosity was too low to be suitable for coating applications.

TABLE I Dry Times of Hydroxyl Functional Alkyd Resins and AcrylateFunctionalized Alkyd Resins Hydroxyl Acrylate Hydroxyl AcrylateFunctional Functionalized Functional Functionalized Alkyd Alkyd AlkydAlkyd Film Test Resin 1 Resin 1 Resin 2 Resin 2 Tack Free 2.5 hr. 1.5 hr4 days 4 hr Through Dry 8 days 3 hr 10 days 7 hr Zapon Tack >6 days 30hr weeks 6 days Free Tack Free: cotton test; Through Dry: thumb test;Zapon Tack Free: measured for 45 sec.

It should be understood that the foregoing discussion and examplesmerely present a detailed description of certain preferred embodiments.It will be apparent to those of ordinary skill in the art that variousmodifications and equivalents can be made without departing from thespirit and scope of the invention. All the patents, journal articles andother documents discussed or cited above are herein incorporated byreference.

The claimed invention is:
 1. An ambient oxidative cure compositioncomprising: (a) an acrylate functionalized alkyd resin comprising thereaction product of: (i) a carboxyl functional alkyd resin; and (ii) aglycidyl acrylate wherein the glycidyl moiety of the glycidyl acrylateis the reactive moiety and the reaction product contains terminalreactive acrylate moieties; (b) at least one drier; and (c) an organicsolvent.
 2. An ambient oxidative cure composition of claim 1, wherein(a) the acrylate functionalized alkyd resin is present in about 50 toabout 80 wt % based on the total composition; (b) the drier is presentin about 0.01 to about 1.0 wt % based on the total composition; and (c)the organic solvent is present in about 10 to 50 wt % based on the totalcomposition.
 3. An ambient oxidative cure composition of claim 1,wherein the acrylate functionalized alkyd resin comprises the reactionproduct of: (i) about 87 to about 97 wt % of the carboxyl functionalalkyd resin; and (ii) about 3 to about 13 wt % of the glycidyl acrylate,wherein the weight percents are based on the total weight of (i) and(ii).
 4. An ambient oxidative cure composition of claim 1, wherein thecarboxyl functional alkyd resin comprises the reaction product of ahydroxyl functional alkyd resin and an acid anhydride, wherein thehydroxyl functional alkyd resin comprises: (a) 0 to about 30 mole % of adiol; (b) about 10 to 40 mole % of a polyol; (c) about 20 to 40 mole %of a diacid; (d) 0 to about 10 mole % of a monofunctional acid; and (e)about 10 to about 40 mole % of a fatty acid, fatty ester, or naturallyoccurring-partially saponified oil, wherein the mole percents are basedon the total moles of (a), (b), (c), (d) and (e).
 5. An ambientoxidative cure composition of claim 4, wherein the diol is neopentylglycol, the polyol is trimethylolpropane or pentaerythritol, the diacidis isophthalic acid, isophthalic anhydride or phthalic acid, and themonofunctional acid is benzoic acid.
 6. An ambient oxidative curecomposition of claim 1, wherein the drier is selected from the groupconsisting of salts of cobalt, zirconium, calcium, zinc and manganese.7. An ambient oxidative cure composition of claim 4, wherein thehydroxyl functional alkyd resin has a hydroxyl number of about 80 toabout 180 mg KOH/g.
 8. An ambient cure composition of claim 3, whereinthe glycidyl acrylate is glycidyl methacrylate.
 9. An ambient oxidativecure composition of claim 1, further comprising at least one additiveselected from the group consisting of flow control agents, extenders,plasticizers, flatting agents, pigment wetting agents, pigmentdispersing agents, ultraviolet (UV) absorbers, UV light stabilizers,tinting pigments, colorants, defoaming agents, antifoaming agents,anti-settling agents, anti-sag agents, bodying agents, anti-skinningagents, anti-flooding agents, anti-floating agents and corrosioninhibitors.
 10. An ambient oxidative cure enamel composition comprising:(a) an acrylate functionalized alkyd resin comprising the reactionproduct of: (i) a carboxyl function alkyd resin; and (ii) a glycidylacrylate wherein the glycidyl moiety of the glycidyl acrylate is thereactive moiety and the reaction product contains terminal reactiveacrylate moieties; (b) at least one drier; (c) an organic solvent; and(d) at least one pigment.
 11. An ambient oxidative cure enamelcomposition the pigment is present in about 30 to about 60 wt % based onthe total weight of the composition.
 12. An ambient oxidative cureenamel composition of claim 11 further comprising at least one additiveselected from the group consisting of flow control agents, extenders,plasticizers, flatting agents, pigment wetting agents, pigmentdispersing agents, ultraviolet (UV) absorbers, UV light stabilizers,tinting pigments, colorants, defoaming agents, antifoaming agents,anti-settling agents, anti-sag agents, bodying agents, anti-skinningagents, anti-flooding agents, anti-floating agents and corrosioninhibitors.
 13. A method of preparing an ambient oxidative curecomposition comprising the step of: reacting a carboxyl functional alkydresin with the glycidyl moiety of a glycidyl acrylate to form anacrylate functionalized resin, and contacting the acrylatefunctionalized alkyd resin with at least one drier in the presence of anorganic solvent.
 14. A method of claim 13, wherein the glycidyl acrylateis glycidyl methacrylate.
 15. A substrate coated with an ambientoxidative cure composition of claim
 1. 16. A substrate coated with anambient oxidative cure enamel composition of claim
 10. 17. A substratecoated with an ambient oxidative cure enamel composition of claim 12.